Well installation for subsuraface hydraulic pumps



Sept. 29, 1953 o. E. DEMPsi-:Y ETAL 2,653,545

WELL INSTALLATION FOR SUBSURFACE HYDRAULIC PUMPS Filed April 7, 1951 3 Sheets-Sheet l 5 ro 7 n O |132 F0 Z982 3 333 3 IN1/Ewan: 0.2'. DEMP u. awooos f In...

TTOFNEY FIG. l

-mi 1/ I HII l I IIII Sept. 29, 1953 o. E. DEMPSEY ET AL 2,653,545

WELL INSTALLATION FOR SUBSURFACE HYDRAULIC PUMPS Filed April 7, 1951 3 sheets-sheet 2 ID E2 llj w n y k IN VEN TORJ` l k a'. MMPSEY TTOPNEY Patented Sept. 29, 1953 WELL INSTALLATION FOR SUBSURFACE HYDRAULIC PUMPS Oscar E. `Dempsey and John B. Woods, Tulsa, Okla., assignors, by mesne assignments, to Byron Jackson Co., Los Angeles, Calif., a corporation of Delaware Application April 7, 1951, Serial No. 219,848

19 Claims. 1

This invention relates to improvements in oil well pumping apparatus, and more particularly, but not by way of limitation, to a subsurface hydraulic pump installation for an oil well, and means for removing and installing the pump in an oil well.

As it is well known, Subsurface hydraulic pumps have been used in oil wells for several years. The prevalent method of installinga hydraulic pump in a well has been to secure the pump on the end of a small string of tubing, commonly called the macaroni string, and inserting the pump and the macaroni string in a larger string of well tubing. The well tubing is in turn disposed in the well casing and extends downwardly in the well casing into communication with the well fluid. The pump is seated in fluid tight engagement with lower portion of the well tubing to provide an annular producing passageway between the macaroni string and the well tubing for the well fluid and the exhausted or spent power fluid utilized to operate the hydraulic pump.

In operation, high pressure power fluid is usually forced downwardly in the macaroni string to operate the hydraulic pump. The well pump in turn pumps the well fluid upwardly through the annular production passageway to the surface of the well. The power fluid, after passing through the engine end of the pump, is usually combined with the well fluid in the production column. As a general rule, for every unit volume of high pressure power fluid forced down the macaroni string, one unit volume of well fluid is drawn into the system by the pump, thus two unit volumes of fluid are recovered at the surface of the well.

It is also well known that most well fluids carry variable amounts of sand, shale, and abrasive oxides from the formation, which, together with pipe scale and other foreign substances contaminating the power oil system, are very destructive to the pumping mechanism. Therefore, the pump must be periodically removed from the well for repair and replacement of parts. In the method of pump installation previously described, the complete macaroni string must be pulled from the well to remove the pump unit. To pull the macaroni string requires the service of several workmen for several hours (depending upon the depth of the well), as well as a portable pulling unit which is ordinarily not present at the well and must be transported from a distant location. Itis readily seen, therefore, that not only is the removal and reinstallation of a pump unit in this manner relatively expensive, but the well must also be shut down for a considerable period of time, resulting in loss of production.

In addition to sand being present in the well fluid, there may also be parailin therein which gradually accumulates and solidies in the producing column and must be periodically removed therefrom. It will be readily appreciated that an abundant accumulation of paraffin in an annular shaped production column would be very dilncult to remove. The subsurface pump is usually raised part way out of the well bore to break loose the paramn, resulting in a loss of production time and involving the services of several workmen and auxiliary equipment.

Another known method of installing a subsurface hydraulic pump in an oil well is by providing two parallel strings of tubing in the well casing communicating at their lower ends. One string of the tubing is of comparatively large diameter and the other is of comparatively small diameter, for example, two inches and one inch respectively. The pumping unit is telescopically disposed in the lower end of the large tubing and is seated therein with the lower or pumping end of the unit in communication with the fluid in the well. In operation, high pressure power fluid is forced down the large tubing by suitable surface equipment to operate the subsurface pump, and the pump in turn pumps well fluid and the exhausted or spent power fluid upwardly thilugh the small tubing to the surface of the we The greatest advantage obtained by use of this type of pump installation is the ease of removal and installation of the pump in a well bore. For removal, it is simply necessary to reverse the flow of fluid in the parallel tubing strings, whereupon the pumping unit will be pumped upwardly through the large tubing to the surface of the well. However, each time the flow in the parallel tubing strings is reversed, as when a soluble plug is forced down the small tubing to remove paraffin therefrom, the pumping unit is removed from its seat, or pumping position, and must be reseated before production of the well can be resumed. Furthermore, a portion of the dirty well fluid invariably enters the engine end of the pumping unit each time the flow in the parallel tubing strings is reversed to damage the intricate hydraulic valve and plunger mechanism therein. Another disadvantage of this type of installation is the resistance to flow of the fluid being pumped. As previously set; forth, the v01- ume of iluid forced to the surface of the well is usually twice the amount forced downwardly to the pump. It is readily seen, therefore, that since the largest volume of fluid must be pumped through the small tubing, the frictional resistance to flow of the pumped well fluid, and exhausted power fluid will be imposed directly on the subsurface pumping unit to materially impair the effectiveness of the unit.

The present invention contemplates a novel subsurface hydraulic pump installation utilizing a large and small string of tubing installed in parallel relation in the casing of an oil well. A hydraulic pumping unit is disposed in a housing at the lower end of the large tubing in communication with the well fluid in such a manner that high pressure power fluid forced down the small tubing operates the pump, and the pump in turn pumps well fluid and exhausted power fluid upwardly through the large tubing to the surface of the well.

A novel extension is provided on the upper end of the pumping unit to receive a retrieving device when it is desired to retrieve the subsurface unit. The retrieving device is adapted to be pumped down the large tubing by a reversal of fluid fiow in the parallel strings of tubing. After the retrieving device is in engagement with the pump extension, and the normal direction of flow is resumed through the parallel strings of tubing, high pressure fluid acts on the lower side of the retrieving device to force the pumping unit upwardly through the large tubing to the surface of the well. The direction of flow in the parallel strings of tubing may be periodically reversed, as when cleaning paraffin from the large tubing,

without affecting the seating of the pump, and "f without forcing dirty well fluid through the engine end of the pump. Furthermore, all valves for controlling the flow of fluid at the lower end of the well are retrevable without pulling the well tubing.

An important object of this invention is to provide for the minimum frictional resistance to flow of fluid being pumped by a subsurface hydraulic pump from an oil well in order to increase the overall pumping efficiency.

Another object of this invention is to provide a subsurface hydraulic pump installation utilizing two parallel strings of tubing whereby the direction of flow in the tubing strings may be reversed without affecting the seating of the pumping unit disposed at the end of one string of tubing.

It is another object of this invention to provide a subsurface hydraulic pump installation in such a manner that parain may be easily and efficiently removed from the production column without affecting the seating position of the pump.

A further object of this invention is to preclude the introduction of paraffin into the pumping unit.

A still further object of this invention is to prevent the forcing of dirty well fluid into the engine end of a subsurface fluid actuated pumping unit, when flow of fluid is reversed, or when the pump is being removed from the well.

Another object of this invention is to provide a hydraulic pump installation utilizing a large and a small string of tubing wherein the smaller volume of power fluid flows through the smaller tubing and the greater volume of fluid, consisting of spent power fluid and displaced well fluid, flows through the larger tubing.

Another object of this invention is to provide a hydraulic pump installation for an oil well utilizing a housing secured to the lower ends of two variable sized parallel strings of tubing, wherein the pump is removed and inserted in the well through the larger of the two parallel strings of tubing, but is completely disposed in the housing below the larger string of tubing when in operating position.

A further object of this invention is to provide a hydraulic pump installation utilizing two parallel strings of tubing and a pump housing communicating with the lower ends of each of the tubings having a greater internal diameter than either of the tubings.

Another object of this invention is to provide a subsurface hydraulic pump installation wherein all valves disposed in the well are removable without pulling the well tubing.

-An additional object of this invention is to provide a housing for a subsurface hydraulic pump so constructed and arranged that high pressure power fluid introduced into the housing for operating the pump cannot develop sufficient axial thrust to force the pump out of the housing. Also, to provide such a housing and pump whereby the pump may be removed from the housing only by the connection of a proper tool to the pump, whereupon the high pressure power fluid being introduced into the housing in the same manner as for operating the pump coacts with the tool to remove the pump from the housing.

Other objects and advantages of the inven tion will be evident from the following detailed description, read in conjunction with the accompanying drawings, which illustrate our invention.

In the drawings:

Figure l is an elevational view, partially in section, of the upper portion of a subsurface hydraulic pump installation constructed in accordance with this invention.

Figure 2 is a continuation of Fig. 1 and illustrates the lower portion of the installation and discloses a novel pump chamber having a. subsurface hydraulic pump disposed therein.

Figure 3 is a sectional view of the upper portion of the hydraulic pump installation, partially diagrammatically shown for clarity.

Figure 4 is a continuation of Figure 3 and illustrates the upper portion of the hydraulic pump.

Figure 5 is a continuation of Figure 4 and illustrates the lower portion of the hydraulic pump.

yFigure 6 is a continuation of Figure 5 and illustrates the standing valves at the lower end of the pump installation.

Figure 7 is an elevational View, partially in section, of a novel retrieving device for removing the subsurface pump unit.

Figure 8 is an elevational view, partially in section, of a wire line grappling member.

Referring to the drawings in detail, and particularly Fig. 1, reference character i designates the usual casing head provided at the upper end of the well casing 2. The well casing 2 extends downwardly in the well bore 3 to the producing sands (not shown). A pair of tubing strings l and 5 are secured in the casing head I and extend downwardly in the casing 2 in parallel relationship. The upper end 6 of the larger tubing string 4 is enclosed by a cap l for purposes as will be hereinafter set forth. The upper end 8 ofthe smaller tubing string 5 is interconnected by a conduit 9 to a suitable four-way valve I0 having the usual handle H. The opposite side of the valve Ill is connected by a conduit I2 to an intermediate portion of the tubing string 4 above the casing head I.

A supply conduit I3, and a discharge conduit I4 are also connected to the valve I0. The conduit I3 communicates with a suitable hydraulic surface pump (not shown) utilized to supply clean power fluid, preferably oil, tof the valve I). The conduit 'Ill communicates with a suitable storage tank or the like (not shown) for receivingthe fluid displaced from the well bore 3. It will be understood that the valve I9 may be manually operated by turning the handle Il tol place the conduit I3 into communication with either conduit 9, or I2, yand simultaneously placing conduit I4 into communication with either conduit I2 or 9.

The tubing string 4 forms the production column for the installation and extends downwardly into proximity with the lower end (not shown) of the casing 2, and has a novel housing I5 (Fig. 2) suspended from the lower end I5 thereof. An essentially cylindrical pump cavity il' is provided in the housing I5 to receive a subsurface hydraulic pump IB. The diameter of the cavity Il is larger than the internal diameter of the tubing e for purposes as will be hereinafter set forth. Vertically spaced circumferential shoulders I9 and 20 extend into the pump cavity Il to engage sealing rings 2! rand 22, respectiva ly, carried by the pump unit i8. Therefore, when the pump I8 is installed in the cavity Il' as shown in Figure 2, the cavity I'I is divided into three chambers 23, 24 and 25.

The lower end 2G of the small tubing string 5 is connected to an intermediate header 2l of the housing I5 disposed below the lower end It of the tubing string 4. A passageway 2S is provided in the header 27 providing communication between the lower end 2t of the tubing 5 and the centrally disposed chamber 24 of the pump cavity Il. Another passageway 29 in the header 2l provides communication between the upper chamber 23 and la conduit 38 also connected to the header 21. The lower end 3l of the conduit 3@ is connected to a lower header 32 of the housing I5, and communicates through a passageway 33 with the lower pump cavity chamber 25. Communication is therefore constantly provided between the large tubing string 4, the upper chamber 23 and the lower chamber 25, as well as between the small tubing string 5 and the central or intermediate chamber 24.

A conduit Sil extends from the lower header 32 of the housing I 5 in aligned relationship with the lower chamber to provide a seating nipple for the pump unit I8. A bleeder type standing valve unit 35 is provided in the seating nipple Scl below the pump unit I8, as will be more fully hereinafter set forth. A conduit 3G of larger diameter is also suspended from the lower end 32 of the housing I5, and is perforated as clearly shown in Figure 2 toprovide pass-ageways for well fluid (not shown) to flow from the casing 2 into the conduit 34.

1t will be understood that the housing It may may be constructed in one unit as shown, or may be formed from a plurality of elements (not shown) according to the dictates of the manufacturer. The housing I5 is illustrated as one unit merely `for simplicity. v

As clearly shown in Figures 4 and 5, the pump unit I8 comprises an enginepisto-n 3l and a pumping piston 39 interconnected by a hollow rod 39. The engine piston 3l, pump piston 3S and hollow rod 39 are preferably similar .to those 6. elements as shown in applicants copending application, Serial No. 90,953, entitled Hydraulic Pump, filed May 2, 1949, now Patent No. 2,631,541. The elements provided in the engine piston 3l and the pump piston 38 are therefore not shown in detail herein. A main valve (not shown) and a pilot valve (not shown) are carried in the engine piston 37 to: control the application of high pressure power uid to the engine piston and hence the operation of they pump I8. The usual traveling valve (not shown) is carried in the pump piston 38 to preclude flow of fluid downwardly through the piston but permit flow of fluid upwardly through the piston.

I'ihe engine piston 31 reciprocates in a tubular engine cylinder 4l] and the pump piston 38 reciprocates in a pump cylinder lil. The cylinders 49 and 4I are interconnected by an apertured middle plug 42 (Fig. 5) through which extends the hollow rod 39. The sealing rings 22 yare carried by the middle plug 42, and are adapted to engage the seating shoulder 2li as previously set forth. A plurality of circumferentially spaced apertures 43 are provided transversely in the upper end 44 of the middle plug 42 Iand establish communication between the central pump cavity chamber 24 and the lower end of the engine cylinder 49. Suitable packing 49 is provided in the apertu-red middle plug 42 around the rod 39 in the usual manner. A plurality of transverse apertures 45 are also provided in the upper end of the pump cylinder 4I to establish communication between the upper portion of the pump cylinder 4I and the lower pump cavity chamber A standing valve unit 4l (Fig. 6) is threadedly secured on the lower end 48 of the pump cylinder ll-I and comprises a valve body 49 having a valve seat 5b therein. A ball type valve 5I cooperates with the valve seat 59 to preclude flow or fluid downwardly through the valve unit 4l. A valve cage 52 is provided in the body t9 above the ball valve 5I to limit the upward movement of the ball valve 5I when fluid iiows upwardly through the valve unit 4l.

rhe valve seat 5c is secured in the body t9 by a threaded sleeve 53 having an outwardly projecting annular flange 54 on the lower end thereof. The flange 54 normally rests on an apertured cap-shaped member 55 secured to the upper end of a tubular mandrel et. A smaller sized sleeve 5l is secured in the sleeve 53 and extends downwardly through the apertured cap 55. A suitable sealing ring 53 provides a iiuid tight seal between the sleeve 5I and the apertured cap 55. The sleeve 51 may be moved relative to the cap 55, as will be hereinafter set forth. A circumferential flange 5g is provided on the lower end of sleeve 5l to limit its relative upward movement. A plurality 4of circumferentially spaced apertures Sli are provided in the sleeve `5l to provide communication between the lower pump cavity chamber and internal bore of the tubular mandrel 55 when the sleeve 5l is in its uppermost position (not shown) When the sleeve 5? is in its normal operating position as shown in Figure 6, the apertures 59 are disposed below the sealing ring 58, thereby precluding communication between the chamber 25 and the mandrel 56.

lA conical seating surface 6I is provided on the outer periphery of the tubular mandrel 55 and cooperates with a conical shaped seat 62 provided in the lower end 92 of the housing I5 to position the pump unit I3 in the pump cavity Il. A plurality of sealing cups '63 are secured on the outer 7 periphery of the mandrel 56 in the usual manner to cooperate with the nipple 34 and anchor the pump unit 8 in the cavity I1.

As previously set forth, a standing valve unit 35 is also provided in the downwardly extending nipple 34. The valve unit 35 comprises a valve body 64 adapted to rest on an inwardly projecting circumferential flange 65 provided in the lower portion of the nipple 34. A valve seat 66 is secured in the lower end of the valve body 64 by a threaded sleeve 61. A ball type valve 68 cooperates with the valve seat 66 to preclude flow of fluid downwardly through the body 64. The ball 68 moves upward when a suction is created in the nipple 34 by action of the pump unit I8 to permit flow of fluid upwardly through the valve body 64. The upward movement of the ball l68 is limited by a valve cage 69 secured in the body 64.

A tubular mandrel 10 is threadedly secured to the upper end of the valve body A64 and has a plurality of sealing cups 1| secured on the outer periphery thereof in the usual manner to anchor the valve unit 35 in the seating nipple 34. An inwardly projecting hollow knockout plug or pin 12 is threadedly secured in an aperture 13 provided in the central portion of the valve body 64. The plug 12 may be broken off upon the insertion of a tool in the valve unit 35 as will be more fully hereinafter set forth to permit removal of the valve unit 35 from the well.

The upper end 14 (Fig. 4) of the engine cylinder 48 is enclosed by an apertured plug member 15 having an upwardly extending tubular portion 16. The sealing rings 2| are secured on the tube 16 and cooperate with the shoulder I9 to separate the upper pump cavity chamber 23 from the intermediate chamber 24 as previously set forth. A plurality of circumferentially spaced apertures 11 are provided in the plug 15 to establish communication between the chamber 24 and the tube 16 for purposes as will be hereinafter set forth. A smaller sized tube 18 extends upwardly from the plug 15 within the tube 16 and is enclosed at its upper end 19 (Fig. 3). The pilot valve rod 8i) (Fig. 4) of the engine piston 31 extends upwardly through the apertured plug 15 into the tube 18 and is actuated in the same manner as in said previously mentioned copending application.

A valve housing 8| (Fig. 3) is threadedly secured to the upper end 82 of the tube 16. A valve seat 83 is secured in the valve body 8| to receive a ball type valve 84. A circumferential shoulder 85 is provided in the lower portion of the valve body 8| to limit the downward movement of the ball 84. A sleeve 86 is secured to the valve body 8| and extends upwardly therefrom for connection with a tubular element B1. The sleeve 86 is also utilized to secure an upturned sealing cup 88 on the member 81. A plurality of circumferentially spaced apertures 89 are provided in the sleeve 85 to establish communication between the valve body 8| above the valve sea-t 83 and the upper pump cavity chamber 23. A rod 90 is reciprocally disposed in the tubular member 81 and is adapted to retain the ball valve 84 off of the seat 83 in one position thereof as will be hereinafter set forth. The rod 90 is precluded from being forced upwardly out of the member 81 by a head 9| provided in the central portion thereof. A conical shaped head 92 is provided on the upper end of the tubular member 81.

Operation.

Assuming the pump unit I8 is seated in the cavity I1 as shown in Figures 2 to 6 and the valve I0 is set as shown ln Figure 3, high pressure power fluid being pumped through the conduit I3, in the direction of the arrow, will be directed through the conduits 9, power tubing 5, and passageway 28 (Fig. 4) into the central chamber 24 of the pump cavity I 1. From the chamber 24, the vpower fluid flows in two directions. Firstly, the power fluid ows through the apertures 11 and the tube 16 into the valve body 8| (Fig. 3) to retain the ball 84 upwardly against the seat 83. The power fluid in chamber 24 also flows through the apertures 43 (Fig. 5) into the lower end of the engine cylinder 40 to operate the hydraulic pump Il. The pump I8 operates in the same manner as in the above-mentioned copending application, and the power fluid, after acting on the engine piston 31, is exhausted downwardly through the hollow middle rod 39 and thence upwardly through the pump piston 38 into the upper portion of the pump cylinder 4|.

During the upstroke of the pump plunger 38, a suction is created in the lower end of pump cylinder 4| (Fig. 6) and the seating nipple 34, causing a flow of well fluid from the well bore 3 upwardly through the standing valve unit 35 and the valve body 41 into the lower portion of the pump cylinder 4|. On the downstroke of the pump plunger 38 (Fig. 5), well fluid previously drawn into the lower end of the pump cylinder 4| is forced through the pump plunger 38 and out through the apertures 53 into the upper portion of the pump cylinder 4| to mix with the .exhausted or spent power fluid from the engine 31 previously discharged through the hollow rod 39, and apertures 93. It will be noted that the ball valves 5I and 58 (Fig. 6) are seated on their respective seats 58 and 66 during the downstroke of the pump plunger 38 to preclude a retrograde flow of the well fluid downwardly through the seating nipple 34.

On the subsequent upstroke of the pump plunger 38, the travelling valve (not shown) carried thereby will close, and the plunger 38 will displace the combined well fluid and exhausting power fluid out of the cylinder 4| through the apertures 48 into the lower pump cavity chamber 25 (Fig. 5). From the chamber 25 the fluid will be forced through the passageway 33 (Fig. 6), conduit 30 and passageway 29 (Fig. 4) into the upper pump cavity chamber 23. The pumped fluid will then flow upwardly through the large production tubing 4 (Fig. 3), conduit I2, valve I8 and conduit I4 to a desired storage (not shown).

From the foregoing it is apparent that during the normal operation of the pump unit I8 (Fig. 2), the smaller volume of high pressure power fluid will flow through the smaller power tubing 5, and the larger volume of production fluid, being a combination of pumped well fluid and exhausted or spent power fluid, will flow through the larger production tubing 4. The frictional resistance to flow of the production fluid will therefore be maintained at a minimum, thereby imposing a minimum load on the subsurface pump unit i8 and providing a more efficient well pumping installation. Furthermore, the weight of the column of fluid in the production tubing 4 will continuously press downward on the pump unit I8 to retain the pump in its seated position during operation thereof, as shown in Fig. 2.

Pump removal To facilitate the removal of the pump unit I8, asuitable pump catcher 84 (Fig. 3) is disposed in the upper end 6 of the large tubing string 4, and is retained therein by the cap 1. The pump catcher 94 comprises a cylindrical body portion 95 having a slip chamber 95 therein. A head 91 is disposed in the chamber 06 and is provided with a plurality of pins 98 extending radially therefrom. A slip 09, having an inwardly projecting head on the lower end thereof, is loosely secured on each pin 08 to catch the pump unit 8 as will be hereinafter set forth. The slips 00 are forced inwardly by the tapering walls |0I of the chamber 06 when in va down position as shown in Fig. 3. A rod |02 extends upwardly from the head 01 into a bore |03 to retain the slips 09 in alignment with the chamber 96.

A retrieving device I 04 (Fig. '1) is provided for removing the pump unit I8. The retriever |04 comprises a cylindrical mandrel |05 having three (but not limited thereto) sealing cups |05, |01 and |08 suitably secured on the outer periphery thereof. The upper two cups |55 and |01 are turned downwardly, and the lower cup |08 is turned upwardly for purposes as will be hereinafter set forth. A housing |09 is threadedly secured, through the medium of a sleeve 0, to the lower end III of the mandrel |05. A head I I2 is disposed in the housing |09 and has a plurality of pine |I3 extending outwardly therefrom. A slip member |I4, having an inwardly projecting head II on the lower end thereof, is loosely secured on each pin I|3. The slips ||4 are retained in contact with each other by the tapered inner walls I5 of the housing |09 when the slips |I4 yare in a down position as shown in Figure '7. A rod II1 projects upwardly from the head |I2 and is reciprocally disposed in a bore ||8 of the sleeve I I0 to retain the slips ||4 in alignment in the housing |09 during movement thereof. A helical spring |I9 is disposed on the rod |I1 and co-acts with the sleeve ||0 to yieldably retain the slips IIA in a down position as shown. A conical shaped head |20 is provided on the upper end of the mandrel |05 for purposes as will be hereinafter set forth.

When it is desired to remove the pump unit I 8, the cap 1 and pump catcher 94 (Fig. 3) are removed to permit insertion of the retriever |04 into the upper end 46 of the tubing 4. The retriever |04 is inserted in the tubing 4 in an upright position as shown in Figure '1, and forced manually downward below the interconnection of the conduit l2 and tubing 4. The pump catcher 94 and cap 1 may then be replaced without interference with the retriever |04. The valve I0 is then turned to direct the high pressure fluid from the conduit I3 into the conduit I2 and hence into the upper portion of the tubing Il. The high pressure fluid will 'act on the upturned cup |00 of the retriever |00 and force the retriever downwardly in the large tubing Il, it being understood that the cup |08 is forced outwardly into sealing relationship with the tubing 4.

rl'he combined well fluid and exhausted power fluid standing in the tubing 4 will be forced downwardly through the tubing 4 by the retriever Iiifl and flow inwardly through the apertures 09 (Fig. 3) into the sleeve 80 above the valve body 0|. The ball valve 84 will thereby be forced downwardly into unseating position, permitting the downwardly moving fluid to flow through the valve seat 03, valve body 8|, tube 10 and apertures 11 (Fig. 4) into the central pump cavity chamber 24. Since the lower chamber 25 also communicates with the tubing 4 through rpassageway 33 (Fig. 6), conduit 30 and passageway 29 (Fig. 4), the fluid pressure on both sides of the pump is equalized. Therefore, operation of the pump unit I8 will be stopped. In this condition, the clean power fluid stagnant in the central chamber 24 will not discharge through the engine piston 31, but is displaced by the downwardly moving dirty fluid through the passageway 28 and tube 5, since the tubing 5 is then at low pressure by virtue of the position of the four way valve I0. In like manner, the previously pumped dirty fluid in tubing 4 being forced downwardly by the retriever |04 will not enter the engine piston 31, but will be forced through the central chamber 24, thence through the passageway 28 (Fig. 4), tubing 5, conduit 9 (Fig. 3), Valve I0 and conduit I4 to storage.

As the retriever I 04 reaches the pump unit I8, the housing |09 of the retriever |04 moves over the conical shaped head 92 (Fig. 3). The head 92 will thereby become engaged by the slips 4, and the head ||2 of the retriever |04 will move the rod downwardly to hold the ball 84 off of the seat 83. The valve I0 is then turned back to the position shown in Figure 3 to again direct the high pressure power fluid through conduit 9, tubing 5, and passageway 28 into the central chamber 24 (Fig. 4). Since the ball 84 (Fig. 3) is then retained off of the seat 83 by the rod 90, the high pressure fluid will flow from the chamber 24 (Fig. 4) through the apertures 11, tube 16, valve housing 8|, apertures 89, and chamber 23 into the lower end I6 of tubing 4. The high pressure fluid will then act on the downturned cups |06 and |01 of the retriever |04, forcing the retriever in an upward direction to unseat the pump unit I 8. The pressure of the power fluid will be sufficiently high that the force exerted on the exposed annular area of the inverted cups |06 and |01 will overcome the weight of the column of fluid in the tubing 4 and initially raise the retriever |04 and the pump unit I8.

It will be noted that the chamber 23 communicates with the lower chamber 25 through the passageway 29, conduit 30 and passageway 33. Therefore, the pressure of the power fluid will be exerted in the lower chamber 25 and act downwardly on the sealing cups 63 (Fig. 6). Furthermore, the pressure in the seating nipple 34 below the seating cups 63 will be equal to the well pressure and therefore relatively low as compared to the pressure of the power fluid. It will therefore be apparent that upward movement of the mandrel 56 will be retarded. However, the sleeve 51, being rigidly connected to the pump cylinder 4|, will be moved upward through the cap 55 during the initial upward movement of the pump unit I8. When the lower flanged end 59 of the sleeve 51 contacts the cap 55, the high pressure fluid will flow from the chamber 25 through the apertures 60 and mandrel 56 into the seating nipple 34 to equalize the pressure above and below the cups 63 and facilitate removal of the mandrel 56. The lower standing valve unit 35 will prevent flow of the fluid downwardly out of the nipple 34. When the mandrel 56 has been moved upwardly into the chamber 25, the high pressure fluid will act on the entire cross sectional area of the pump unit I8 as well as the exposed area of the cups |06 and |01 (Fig.

1 1 '7) to provide a speedy upward movement of the pump unit I8 through the tubing 4.

As the pump unit I8 and retriever |04 approach the upper end 6 of the tubing 4, the conical shaped head |20 enters the pump catcher 94 (Fig. 3) and is engaged by the slips 99. To remove the pump unit I8 it is then simply necessary to remove cap 1 and lift the pump catcher 94, retriever |04 and pump unit I8 out of the tubing 4.

A boss |22 is provided on the tubing 4 adjacent the upper end 6 thereof. A plunger rod |23 is reciprocally disposed in the boss |22 and may be pushed partially into the tubing 4, except when the pump unit I8 is disposed in the upper portion of the tubing 4. Suitable packing (not shown) is provided in the boss |22 around the rod |23 to prevent a leakage of fluid from the tubing 4. A helical spring |24 is also provided in the boss |22 around the rod |23 to normally retain the rod |23 in a retracted position from the tubing 4 as shown in Figure 3. By manual operation of the rod |23 the presence or absence of the pump unit I8 in the upper portion of the tubing 4 can be ascertained.

From the foregoing it is apparent that when the ow of uids in the parallel tubing strings 4 and 5 is reversed for any reason, thereby obtaining a higher fluid pressure in the lower end I6 of the tubing 4 than in the lower end 26 of the tubing 5, the pump unit I8 remains in its seated position in the pump cavity I1 and the diria wel)v fluid is not forced through the engine piston 31 to damage the delicate valve mechanism (not shown) therein. The pump I8 can only become unseated and removed from the well when the retriever device is disposed in tube 4 in connection with the element 92 and the normal fluid flow through tubes 5 and 4 is resumed. It is also apparent that upon flow reversal a soluble plug (not shown) may be pumped down the large tubing 4 to remove paraffin by liquecation due to change in temperature and pressure, without affecting the seating position of the pump unit I8.

When it is desired to install the pump unit I8, the pump is inserted in the upper end 6 of the tubing 4 in an upright position as shown in Figure 2 and the pump catcher 94 and cap 1 are replaced. The valve I is then turned to direct high pressure power fluid from the conduit I3 through the conduit I2 into the tubing 4. The high pressure fluid will then act on the upturned cup 88 (Fig. 3) to force the cup 88 outwardly into sealing contact with the inner periphery of the tubing 4, and force the pump unit I8 downwardly in the tubing 4. As previously set forth, the diameter of the pump cavity I1 is greater than the internal diameter of the tubing 4, therefore as the cup 88 enters the upper chamber 23, the pressure on opposite sides of the cup 88 will be equalized to render the cup 88 inoperative for assisting the movement of the pump unit I8 downwardly. However, when the cup 88 enters the chamber 23, at least one of the cups 2| (Fig. 4) will have contacted the shoulder I9, also one of the cups 22 (Fig. 5) will have contacted the shoulder 20 and one of the cups 63 (Fig. 6) will have entered the seating nipple 34. The pump cavity I1 will therefore be divided into the three chambers 23, 24 and 25, the same as when the pump unit I8 is fully seated.

The valve I0 is then again turned to the position shown in Fig. 3 to direct the high pressure power fluid through the small tubing and into the central chamber 24 to operate the pump unit I8 in the usual manner. During the iirst upstroke of the pump plunger 38, a suction will be created in the seating nipple 34. The weight of the column of oil standing in the tubing 4 and acting on the pump unit I8 will then force the pump unit I8 downwardly to the fully seated position as shown in Figs. 2 and 6. It will be readily seen that during downward movement of the pump unit I8, the cap 55 will be retained in contact with the ange 54 due to fluid standing in the cavity I1 and resisting movement of the pump unit I8. Therefore, when the pump unit I3 is partially seated, the sealing ring 58 is disposed above the apertures 60, to preclude flow from the chamber 25 through the ports 60 during the first upstroke of the pump plunger 38 and assure the creation of a suction in the seating nipple 34 to assist the final seating of the pump unit I8.

It is sometimes necessary to remove the lower standing valve unit 35. A suitable grappling member |26 is illustrated in Fig. 8 and is utilized for this purpose. The grappling member |26 comprises a rod |21 threaded at its upper end I 28 for connection with a wire line connector (not shown). A sleeve |29 is threadedly secured to the lower end |30 of the rod |21 and has a dog I3| provided therein. A head |32 is provided on the lower end of the dog I3I and normally extends outwardly through an aperture |33. The dog I3| is yieldably retained in a down position as shown in Figure 8 by a suitable spring |34.

Assuming the pump unit I8 has been removed from the well and it is desired to remove the standing valve unit 35, the grappling member |213 is lowered through the tubing 4 by use of a suitable wire line or the like (not shown). As the sleeve |29 moves through the mandrel 10, the lower end of the sleeve |29 contacts and breaks oil' the knockout plug 12 to expose the aperture 13. The column of fluid standing in the large tubing 4 and the small tubing 5 is then drained through the mandrel 10, aperture 13 and around the lower portion of the valve housing 64 out of the lower end of the seating nipple 34 into the well casing 2. As the dog I3I is moved downwardly through the mandrel 10, the dog is retracted against the action of the spring |34 to move the head |32 into the sleeve |29. When the dog head |32 has moved below the mandrel 10, the spring |34 moves the head |32 outwardly for engagement with the lower end of the mandrel 10 upon a subsequent upward movement of the grappling member |26. After the tubings 4 and 5 have been drained, the standing valve unit 35 may be freely removed through the tubing 4.

From the foregoing it is apparent that the present invention provides a novel subsurface hvdraulic pump installation wherein the minimum frictional resistance to iiow is generated by the fluid being pumped from the well to reduce the load imposed on the subsurface pump to a minimum and increase the overall pumping eiliciency. Two strings of tubing are provided in the well bore and are interconnected in such a manner that the flow through the tubings can be reversed, as when sending a retrieving device down the well to recover the subsurface hydraulic pump unit, or a soluble plug is passed downwardly through the production column to remove parafiin therefrom, without affecting the seating position of the pumping unit. Furthermore, the dirty production or well fluid will not be forced through the pump unit to damage the intricate valve mechanism therein, when the flow of fluid in the parallel strings of tubing is reversed. When the retrieving device is passed downwardly through the production column, paraffin which may be present therein is forced downwardly to a depth where the paraffin will become liqueed. Therefore, when the subsurface pump unit is subsequently raised through the production column, solidified paraffin is not forced from the production column into the various piping connections at the surface of the well t impair the flow of fluid therethrough. It is also apparent that the present invention provides a novel pump installation wherein all valves provided in the well bore are removable.

Changes may be made in the combination and arrangement of parts as heretofore set forth in the specification and shown in the drawings, it being understood that any modification in the precise embodiment of the invention may be made within the scope of the following claims without departing from the spirit of the invention.

We claim:

1. In a well installation for a subsurface hydraulic pump, comprising a large tubing and a small tubing extending downwardly in the well, a housing secured to the lower end of the large tubing for the reception of the subsurface pump constructed and arranged to provide communication between the power inlet of the subsurface pump and the small tubing and betraf-een the cutlet of the subsurface pump and the large tubing, whereby power uid iiowing down the small tubing will operate the subsurface pump and the fluid pumped by the subsurface pump will flow up the large tubing, a passageway in the subsurface pump providing a by-pass passageway for fluid upon a reversal of flow in the large and small tubings, a check valve in the passageway to preclude flow of fluid from the small tubing through the passageway into the large tubing, and a retrieving device adapted to engage the upper end of the subsurface pump and open said check valve, whereby fluid will flow from the small tubing through the passageway to act on the retrieving device and raise the subsurface pump through the large tubing.

2. In a well installation for a subsurface hydraulic pump, comprising a large tubing and a small tubing extending downwardly in the well, a housing secured to the lower end o-f the large tubing for the reception of the subsurface pump constructed and arranged to provide communication between the power inlet of the subsurface pump and the small tubing and between the outlet of the subsurface pump and the large tubing, whereby power uid flowing down the small tubing will operate the subsurface pump and the fluid pumped by the subsurface pump will flow up the large tubing, a passageway in the subsurface pump providing a by-pass passageway for fluid upon a reversal of flow in the large and small tubings, a check valve in the passageway to preclude flow of fluid from the small tubing through the passageway into the large tubing, a retrieving device adapted to move in the large tubing and adapted to engage the upper end of the subsurface pump, sealing rings carried by the retrieving device in sealing contact with the large turbing, means for opening the check valve upon engagement of the retrieving device with the pump, whereby fluid may flow from the small tubing through the passageway underneath the sealing rings and raise the subsurface pump through the large tubing.

3. In a, well installation for a subsurface hydraulic pump, comprising a large tubing and a small tubing extending downwardly in the well, a housing secured to the lower end of the large tubing for the reception of the subsurface pump constructed and arranged to provide communication between the power inlet of the subsurface pump and the small tubing and between the outlet of the subsurface pump and the large tubin-g,'whereby power uid owing down the Small tubing will operate the subsurface pump and the fluid pumped by the subsurface pump will flow up the large tubing, a passageway in the subsurface pump providing a by-pass passageway for fluid upon a reversal of flow in the large and small tubings, a check valve in the passageway to preclude flow of fluid from the small tubing through the passageway into the large tubing, a rod carried by the subsurface pump and adapted to open the check valve in one position thereof, a retrieving device adapted to engage the upper end of the subsurface pump and retain said rod in said one position, whereby fluid from the small tubing will flow through said passageway into the large tubing upon engagement of the retrievin-g device, and a sealing cup on the retrieving device disposed in sealing contact with the large tubing when fluid is flowing from the small tubing through the passageway to raise the subsurface pump in the large tubing.

4. In a well installation for a subsurface hydraulic pumpcomprising a large tubing and a small tubing extending downwardly in the well from the surface thereof, a pump cavity communicating with the lower end of the large tubing, a seating nipple communicating with the lower end of the pump cavity for seating a subsurface pump in the pump cavity, a pair of vertically spaced shoulders in the pump cavity, sealing cups carried by the subsurface pump and adapted to contact the shoulders to divide the pump cavity into two chambers, one of said chambers being in communication with the power inlet of the subsurface pump, the other of said chambers being in communication with the outlet of the subsurface pump, a passageway between the rst mentioned chamber and the small tubing to transfer power fluid from the small tubing to the power inlet of the subsurface pump,

and a passageway between the second mentioned ychamber and the lar-ge tubing whereby fluid pumped by the subsurface pump will be pumped through the large tubing to the surface of the well, an extension on the upper end of the subsurface pump, a passageway in said extension providing a by-pass passageway for fluid from the large tubing into the first mentioned chamber upon a reversal of flow in the large and small tubings, a check valve in said last mentioned passageway to preclude flow of fluid therethrough from the first mentioned chamber into the large tubing, a retrieving device adapted to engage the upper end of said extension, and a rod carried in said extension adapted to open the check valve -upon engagement of the retrieving device with 5. A well pump installation comprising first and second tubings extending downwardly within -the well in parallel relation; a fluid-actuated pump unit of a size to pass through said first tubing and having a power fluid inlet, a pump inlet and a pump outlet; a housing secured to the lower ends of said tubings and defining a pump-receiving cavity aligned with said rst tubing whereby said pump unit may be lowered through said first tubing and into operative position in said cavity; cooperating sealing means on said pump unit and said housing dividing said cavity into a power fluid chamber communicating with said power fluid inlet and a pump chamber communicating with said pump outlet; said housing having first passage means providing communication between said pump chamber and said first tubing, and having second passage means providing communication between said second tubing and said power fluid chamber.

6. A well pump installation comprising first and second tubings extending downwardly Within the well in side-by-side relation; a fluidactuated pump unit of a size to pass through said first tubing and having a power fluid inlet, a pump inlet and a pump outlet; a housing secured to the lower ends of said tubings and defining a pump-receiving cavity aligned with said first tubing, whereby said pump unit may be lowered through said first tubing and into operative position in said cavity; first cooperating sealing means on said pump unit and said housing dividing said cavity into an upper chamber communicating with said power fluid inlet and a lower chamber communicating with said pump outlet; second cooperating sealing means on said pump unit and said housing isolating said upper chamber from said first tubing; said housing having first passage means providing communication between said second tubing and said upper chamber, said housing having second passage means providing communication between said lower chamber and said first tubing.

'7. A well pump installation comprising first and second tubings extending downwardly within the well in side-by-side relation; a fluid-actuated pump unit of a size to pass through said first tubing and having a power fluid inlet, a pump inlet and a pump outlet; a housing secured to the lower ends of Said tubings and defining a pump-receiving cavity aligned with said first tubing, whereby said pump unit may be lowered through said first tubing and into operative position in said cavity; first cooperating sealing means on said pump unit and said housing dividing said cavity into an upper chamber communicating with said power fluid inlet and a lower chamber communicating with said pump outlet; second cooperating sealing means on said pump unit and said housing isolating said upper chamber from said first tubing; third cooperating sealing means on said pump unit and said housing isolating said lower chamber from said pump inlet; said housing having first passage means providing communication between said second tubing and said upper chamber, said housing having second passage means providing communication between said lower chamber and said first tubing.

8. An installation as set forth in claim 6, wherein said second passage means includes a conduit communicating at its lower end with the lower portion of said lower chamber and extending upwardly past said lower chamber and said upper chamber, and communicating at its upper end with said first tubing at a point above said second sealing means.

9. An installation as set forth in claim 6,

wherein said second passage means includes a third tubing disposed in substantial alignment with said second tubing, said third tubing communicating at its lower end with the lower portion of said lower chamber and extending upwardly alongside said housing, the upper end of said third tubing communicating with said first tubing at a point above said second sealing means.

10. A well pump installation comprising a first tubing and a second tubing extending downwardly within the well; a housing secured to the lower end of said first tubing and defining a pump-receiving cavity in alignment with said first tubing; a fluid-actuated pump unit of a size to pass through said first tubing and adapted to seat in said cavity, said pump unit including a reciprocating fluid motor having a power fluid inlet and valve-means for causing reciprocation of the motor in both directions by power fluid introduced through said inlet, said pump unit including a pump actuated by said motor and having an inlet and an outlet; said housing having first passage means providing communication between said pump outlet and said first tubing; said housing having second passage means providing communication between said second tubing and said motor inlet.

11. A well pump installation as set forth in claim 10, and including sealing means on said pump unit and on said housing cooperating, upon seating of said pump unit in said cavity, to isolate said first and second passages from each other.

12. A well pump installation as set forth in claim 10, and including sealing means on said pump unit and on said housing cooperating, upon seating of Said pump unit in said cavity, to isolate said second passage means from said first tubing.

13. A Well pump installation as set forth in claim 10, and including sealing means on said pump unit and on said housing cooperating, upon seating of said pump unit in said cavity, to isolate said first and second passages from each other, and including sealing means on said pump unit and on said housing cooperating, upon seating of said pump unit in said cavity, to isolate said second passage means from said first tubing.

14. A well pump installation as set forth in claim 10, and including sealing means on said pump unit and on said housing cooperating, upon seating of said pump unit in said cavity, to isolate said first and second passages from each other, and including sealing means on said pump unit and on said lhousing cooperating, upon seating of said pump unit in said cavity, to isolate said second passage means from said first tubing, and including sealing means on said pump unit and on said housing cooperating, upon seating of said pump in said cavity, to isolate said pump inlet from said first and second passages.

15. A well pump installation comprising a first tubing and a second tubing extending downwardly within the well; a housing secured to the lower end of said first tubing and defining a pump-receiving cavity aligned with said first tubing; a fluid-actuated pump unit seated in said cavity and including a fluid-actuated motor having an inlet and an outlet for power fluid, and a pump operatively connected to said motor and having an inlet and an outlet for pump fluid; first passage means in said housing providing communication between said second tubing and said motor inlet whereby power fluid pumped down said second tubing will actuate said motor; second passage means in said housing providing communication between said motor and pump outlets and said first tubing whereby pump iiuid discharged by said pump and spent power fluid xhausted from said motor are discharged upwardly through said iirst tubing; said pump unit having a by-pass passage therein and a check valve in said passage, said by-pass passage and said check valve providing unidirectional flow oi fluid from said first tubing to said second tubinir and by-passing said motor and pump, said check valve being normally operative to prevent by-pass flow of iiuid from said second tubing to said first tubing through said by-pass passage.

13. A well pump installation comprising a rst tubing and a second tubing extending downwardly in the well; a housing secured to the lower end of said first tubing and defining a pump-receiving cavity aligned with said rst tubing; a huid-actuated pump unit adapted to be lowered through said rst tubing and seat in said cavity, said pump unit comprising a fluid-actuated rnotor having an inlet and an outlet for power iiuid, and a pump operatively connected to said motor and having an inlet and an outlet for pump fluid; sealing means on said pump unit and on said housing cooperating, upon seating of said pump in said cavity, to divide said cavity into a motor chamber communicating with said motor inlet but isolated from said rst tubing and a pump chamber communicating with said pump outlet but isolated from said second tubing; first passage means in said housing providing communication between said pump chamber and said iirst tubing; second passage means in said housing providing communication between said motor chamber and said second tubing; and a check valve controlled by-pass passage in said pump unit providing unidirectional flow from said rst tubing to said motor chamber, said check valve normally preventing ow from said motor chamber through said by-pass passage to said first tubing.

1'7. A. well pump installation comprising a first tubing and a second tubing extending downwardly within the well; a housing secured to the lower end of said iirst tubing and defining a pump-receiving cavity aligned with said first tubing; a uid-actuated pump unit seated in said cavity and including a huid-actuated motor havan inlet and an outlet for power fluid, and a pump operatively connected to said motor and having an inlet and an outlet for pump fluid; first passage means in said housing providing communication between said second tubing and said motor inlet whereby power fluid pumped down said second tubing will actuate said motor; second passage means in said housing providing communication between said motor and pump outlets and said first tubing whereby pump fluid discharged by said pump and spent power uid exhausted from said motor are discharged upwardly through said first tubing; said pump unit having a by-pass passage therein and a check valve in said passage, said by-pass passage and said check valve providing unidirectional flow of fluid from said first tubing to said second tubing and by-passing said motor and pump, said check valve being normally operative to prevent bypass flow oi' fluid from said second tubing to said irst tubing through said by-pass passage, and means for rendering said check Valve inoperative, to thereby permit iiuid flow from said s eOOnd tubing through said by-pass passage to said first tubing.

18. A housing for a fluid-actuated well pump, comprising a hollow body defining a pump receiving cavity; a head member secured to the upper end of said body, said head member having means for securing a rst tubing thereto in alignment with said cavity and for securing a second tubing thereto in laterally offset relation to said cavity; a foot member secured to the lower end of said body; a by-pass conduit extending from said head member to said foot member; a rst passage in said head member providing communication between said second tubing and said cavity, and a second passage in said head member providing communication between the upper end of said by-pass conduit and said cavity at a point spaced above the point of communication of said first passage with said cavity; a third passage in said foot member providing communication between the lower end of said bi1-pass conduit and the lower portion of said cavity; and a sealing surface in said cavity between said points of communication of said rst and second passages with said cavity and adapted to cooperate with seal means on a pump unit, upon seating of said pump unit in said cavity, to isolate said iirst and second passages from each other.

19. A housing for a fluid-actuated well pump, comprising a hollow body defining a pump receiving cavity; a head member secured to the upper end of said body, said head member having means for securing a first tubing thereto in alignment with said cavity and for securing a second tubing thereto in laterally offset relation to said cavity; a foot member secured to the lower end of said body; a by-pass conduit extending from said head member to said foot member; a iirst passage in said head member providing communication between said second tubing and said cavity, and a second passage in said head member providing communication between the upper end of said by-pass conduit and said cavity at a point spaced above the point of communication of said first passage with said cavity; a third passage in said foot member providing communication between the lower end of said by-pass conduit and the lower portion of said cavity; a sealing surface in said cavity between said points of communication of said iirst and second passages with said cavity and adapted to cooperate with seal means on a pump unit, upon seating of said pump unit in said cavity, to isolate said first and second passages from each other; and a second sealing surface in said cavity between the points of communication of said first and third passages with said cavity and adapted to cooperate with seal means on said pump unit to isolate said first and third passages from each other.

OSCAR E. DEMPSEY. JOHN B. WOODS.

References Cited in the flle of this patent UNITED STATES PATENTS Number Name Date 1,568,447 Forsyth Jan. 5, 1926 1,755,661 Paterson Apr. 22, 1930 1,777,981 Mason Oct. '7, 1930 1,981.288 Ross Nov. 20, 1934 2,230,787 Swain Feb. 4, 1941 2,364,600 Church Dec. l2, 1944 2,469,225 Dempsey May 3, 1949 2,568,320 Coberly Sept, 18, 1951 

